If you sleep past Sof Zemin Kerias Shema (the latest time to say Shema in the morning) and you are davening by yourself, do you need to make any change to your prayers?
Missing Zeman for Shema' does not require a change in what you say. If you miss Zeman Tefillah, however, you may no longer recite the blessings that precede and follow Shema'. Why, though, is something of a mystery to me. I have some ideas that could tangentially offer some understanding, but I'm not sure what is the actual reason.
The Talmud (Berachos 10b) rules that, if one misses the time for Shema (the end of the third hour), he has only lost the merit of performing the mitzvah in its proper time, but he may recite the blessings. According to the ruling of the Shulchan Aruch (58:6), this is true only until the end of the fourth hour (Sof Zeman Tefillah) - but afterwards, one may not recite the blessings over the Shema.
What is the reason for this ruling? The time of reading the Shema is based on the time that people awaken in the morning; in an extreme situation,explains the Levush (ibid.), we can consider the end of the fourth hour the time of awakening. The author of the Tosfos Yom Tov (in his Malbushei Yom Tov) questions this assumpttion, insomuch as the Talmud says that the end of the third hour is the latest time of awakening. He proposes instead that the Sages only allowed one extra hour to make up the blessings.
However, many poskim explained that the blessings of the Shema are indeed part of the mitzvah of Tefillah and not Shema. Thus, one may recite them the entire time that one may recite the Shemoneh Esrei- and, while one should recite the Shemoneh Esrei before the end of the fourth hour, since in extreme situations one may say it until noon that is also the final time for reciting the blessings of the Shema (see Rashba to Berachos 11a, Hagahos Chasam Sofer on the Shulchan Aruch ibid., etc.). While the strict halachic ruling is that one may not say the blessings of the Shema after the end of the fourth hour, the minhag in most communities is to say these blessings until noon (Rav Pe'alim II:12, Mishkenos Yaakov 77, Ketzos Hashulchan 19:13, etc.).